coilover vs air suspension

[jethrow6978]

Hello everyone. I just installed the heidts 4 link kit with the 9 inch housing under my 69 firebird. The issue is with coilovers it rides aweful. I am curious if every fbody with coilovers rides this rough. It will bounce you out of the seat on a gravel road. I am using afco single adjustable with the 300 lb springs. My wife swears it rides like a log truck. I was woundering if it would worth switching from coilovers to air suspension with a set of ridetech shockwave shocks or something similiar in the rear. Ride quality is a big factor but budget is also. I still want to be able to do some auto cross and every now and then some strip time. I have plans for a turbo in the future. Also does anyone else with this set up notice alot of body popping due to the design and weak sheet metal of the rear seat area? Any help or info would be greatly appreciated. :help!:

[mitch_04]

Ride quality is, basically, spring rate. A stiffer spring rides rougher, a softer spring rides softer. You want shocks made for the application, not just the car but the suspension as well. An air spring is adjustable, you can have it stiff for race day and soft for everyday. However, as far as looks go, you want to set it so it looks right when you want it to. Adding air pressure for more spring stiffness will raise the car, taking away air will lower it.

I'd call Ridetech with all the information necessary and they could set you up with shocks & springs (coil or air) that will do just what you want. However, it is a give and take, you choose which you want more. Ride quality or cornering performance.

It's more complex than that, of course, but a call to Ridetech should be an eye opener.

[cluxford]

^ this. I have coilovers in my Camaro they are 12 point adjustable QA1's. Rode so stiff almost rattled my teeth out till I played and talked to tech and found that it like setting 3-4 on the front and only setting 2 on the rear (so much softer but still a solid ride). Now it rides nicer than most newer cars. Then in the Buick it has airide. Rode like a pig when i got it. Bouncing as anything. Hit a dip in the road and I would bounce for the next 100 metres. Shocks were completely shot. Replaced them, now so much better. Just have normal shocks in it now, but looking at adjustables. Have Shockwaves up front. As still still a bit soft.

My recommendation. Play with the adjustment on your coilovers. Start at zero move one click take it for a ride. Find the setting that works best. I was amazed at basically best ride being so close to zero adjustment (out of 12 clicks)

[dhutton]

300 pound sounds quite high. Is the ride height OK and where is the adjuster nut? What coilovers setting are you using?

Don

[benno505]

you have 300lbs springs in the back?

my charger which I am guessing is probably slightly heavier at 3780lbs only has 200lbs in the back, that stiffer spring would be causing the feeling your having

[Carl @ Chassisworks]

Call Heidts and ask them to confirm all your shock and spring dimensions. To help them out, take the following measurements with the car on the ground and weighted as it would be going down the road.

- Shock Length, center of top bolt to center of bottom bolt
- Spring Length

They should be able to work it backwards with that info. For what it's worth, most rear suspensions use a 12" spring. Our most popular spring for a handling car is a 175, then a 200. You have 50% more spring rate keeping the shock from doing it's job.

[Rod]

you have a single adjust.....set it to the softest setting and see if that helps.....and yes 300 is a heavy spring but it still will ride well, I use a 300 on my car and for daily driving....its in the settings as long as those shocks are what was recommended for you suspension setup

[marolf101x]

Though it could be the shock settings or the spring rate you need to first make sure the suspension moves freely.
I've seen this a number of times where we have a customer complain of ride quality issues. When we put the vehicle on a lift and begin to raise it the wheels don't move.

I'm not sure what Heidts uses for bushings in their 4-link so here are my recommendations on a number of options:
Rubber: make sure you tighten the bolts with the suspension at ride height. If you do not the bushings will have a preload when you set the car on the ground.
Poly: make sure you have proper lubrication and don't over tighten the bolts.
Swivel Joints (Jonny Joints, ect): make sure you have proper preload on the ball
Rod Ends: make sure both ends are "straight" with each other before you tighten them down. I've seen some where the rod ends were angled in opposite directions and caused bind as soon as the vehicle started to roll in a turn.

With coil overs it's pretty easy to remove the springs, put the shocks back in the car, then move the suspension through any possible situation; full compression, full droop, full roll, etc making sure it moves freely, easily, and doesn't hit anything.

[Classic Nova & Performance]

Great advice Britt!

With coil overs it's pretty easy to remove the springs, put the shocks back in the car, then move the suspension through any possible situation; full compression, full droop, full roll, etc making sure it moves freely, easily, and doesn't hit anything.

If people would do this during normal install it would eliminate/avoid a lot of problems.